1. Field of the Invention
The present invention relates generally to cardboard cartons or like containers. More specifically, the present invention relates to recloseable cardboard cartons which are particularly adapted to storing powdered or granular materials.
2. Description of the Prior Art
In a variety of consumer packaging applications, it is important to have cardboard containers, cartons or the like which are capable of conveniently, yet securely being opened and reclosed repeatedly. The ability to be repeatedly opened and closed down in a lockable manner is particularly important where the container or carton is used for storage of granular or powdered material, such as laundry detergent powder. Various approaches have been undertaken to address the repeated opening and closing/locking requirements by means of carton designs using different types of inter-locking flaps.
One exemplary recloseable carton design, for instance, is the provision of a locking flap which is attached to the front wall of the carton and designed to engage with the inner layer of the frontal skirt panel in order that repeated closing/locking of the carton may be accomplished. A relatively common recloseable carton design merely involves the use of a friction fit between the frontal skirt panel of the container and the corresponding frontal section of a lid which is hingedly attached to the base of the carton.
In such boxed packages or containers, an integral tear strip is generally used as means by which a user may strip open a container which has been packed with the appropriate material and subsequently sealed. Once the carton top or lid has been separated from the base section by delineating the tear strip, the carton is opened by simply lifting the lid up. Subsequently, the carton is reclosed by simply pushing the lid back down to its original position; locking is realized by the friction fit between the lid and the corresponding engaging portion of the carton base--the blank used to form such a recloseable carton is, of course, dimensioned to ensure the requisite frictional engagement between the lid and the carton.
Conventional recloseable cartons of the above-identified type suffer from disadvantages which severely restrict their use in certain consumer packaging applications, particularly where the packaged product constitutes granular or powdered material such as concentrated laundry detergent powder or the like. A major drawback in this regard is the general absence of a positive locking arrangement in combination with a carton design which is conducive to repeated open and reclose operations. More specifically, the friction-fit designs have been found to be unacceptable from a consumer standpoint because of the distinct possibility of the lid opening by itself and leading to spillage of the contents thereof when such a closed carton is tipped over or otherwise disposed at an acute angle.
Another drawback with such recloseable carton designs is the absence of some form of positive indication, either tactile or audible, of the fact that an opened carton has been reclosed adequately in order to realize an effective locking position. It has been determined in this regard that the presence of such tactile or audible feedback indicative of effective locking is desirable because the presence thereof provides consumers with a high "comfort" factor with respect to reclosure. Particularly in applications where the recloseable cartons are used to house granulated material having a restricted storage life once the storage container has been torn open, such positive feedback has been determined to provide an apparent sense of reassurance to consumers as to retention of "freshness" or "safety" of the contained product.
There, accordingly, exists a distinct need for a recloseable, flip-top carton design which overcomes disadvantages of the above type associated with conventional recloseable cardboard cartons. The present invention effectively and conveniently realizes such an improved recloseable carton design.